[PATCH] D25963: [LoopUnroll] Implement profile-based loop peeling

[David Li via llvm-commits]

davidxl added inline comments.


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Comment at: lib/Transforms/Scalar/LoopUnrollPass.cpp:724
     unsigned MaxTripCount, unsigned &TripMultiple, unsigned LoopSize,
-    TargetTransformInfo::UnrollingPreferences &UP, bool &UseUpperBound) {
+    unsigned &PeelCount, TargetTransformInfo::UnrollingPreferences &UP,
+    bool &UseUpperBound) {
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Should PeelCount be a member of UnrollingPreferences class?


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Comment at: lib/Transforms/Scalar/LoopUnrollPass.cpp:887
+  // If the user provided a peel count, use that.  
+  bool UserPeelCount = UnrollForcePeelCount.getNumOccurrences() > 0;
+  if (UserPeelCount) {
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I think all the logic here should probably be wrapped in a helper function "computeOptimalPeelCount".


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Comment at: lib/Transforms/Scalar/LoopUnrollPass.cpp:904
+  if (UP.AllowPeeling && L->getHeader()->getParent()->getEntryCount()) {
+    PeelCount = getPeelCount(L);
+
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getPeelCount looks like a simple wrapper that is only used once. Probably get rid of it.


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Comment at: lib/Transforms/Utils/LoopUnrollPeel.cpp:63
+
+static void cloneLoopBlocksForPeeling(
+    Loop *L, bool FirstCopy, BasicBlock *InsertTop, BasicBlock *InsertBot,
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Is there common utility to do body cloning?


https://reviews.llvm.org/D25963